Light distribution control device and light distribution control method

Abstract

The purpose of the present invention is to provide a technology with which it is possible to extend the time during which the inner circumference of a curved road is irradiated. This light distribution control device comprises an irradiation control unit that controls the irradiation of a first headlight of a vehicle on the basis of a target position and an inner-side reference position when the difference between a first angle between the forward direction of the vehicle and a direction from the vehicle toward the target position and a second angle between the forward direction of the vehicle and a direction from the vehicle toward the inner-side reference position is less than a threshold value, controls the irradiation of the first headlight on the basis of the target position when the difference is equal to or greater than the threshold value, and controls the irradiation of a second headlight on the basis of the inner-side reference position.

Description

[Technical field]

[0001] The present disclosure relates to a light distribution control device and a light distribution control method. [Background technology]

[0002] Technologies have been proposed that control the light distribution of the vehicle's headlights based on the vehicle's future position (e.g., Patent Documents 1 and 2). With such technologies, the headlights illuminate the position the driver wants to check, allowing the driver to drive the vehicle with peace of mind. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4127997 [Patent Document 2] Patent No. 4403848 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the conventional technology, even if it is possible to continue illuminating the vehicle's future position, the inner periphery of the curve is no longer illuminated while the vehicle is traveling on a curve, so there is a problem in that the driver cannot drive while checking the inner periphery of the curve.

[0005] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a technique that makes it possible to extend the time for irradiating the inner periphery of a curved road. [Means for solving the problem]

[0006] The light distribution control device according to the present disclosure is a light distribution control device that controls light distribution from a vehicle using map information, and includes a driving trajectory estimation unit that estimates a driving trajectory on a curved road along which the vehicle will travel in the future based on the map information, a target position setting unit that sets a target position along which the vehicle should travel among the driving trajectory, a first angle calculation unit that calculates a first angle between a forward direction of the vehicle and a direction from the vehicle to the target position, an inner reference position acquisition unit that acquires an inner reference position that is pre-associated with an inner portion of the curve, a second angle calculation unit that calculates a second angle between a forward direction of the vehicle and a direction from the vehicle to the inner reference position, and an illumination control unit that controls illumination of a first headlight of the vehicle based on the target position and the inner reference position when a difference between the first angle and the second angle is less than a threshold value, and controls illumination of the first headlight based on the target position when the difference is equal to or greater than the threshold value, and controls illumination of a second headlight of the vehicle based on the inner reference position. Effect of the Invention

[0007] According to the present disclosure, when the difference between the first angle and the second angle is less than a threshold, illumination of the first headlight of the vehicle is controlled based on the target position and the inner reference position, and when the difference is equal to or greater than the threshold, illumination of the first headlight is controlled based on the target position and illumination of the second headlight of the vehicle is controlled based on the inner reference position. With this configuration, it is possible to extend the time for illuminating the inner circumference of a curved road.

[0008] The objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram for explaining a driver's general line of sight and driving when the vehicle enters a curved road. [Diagram 2] 1 is a block diagram showing a configuration of a light distribution control device according to a first embodiment. FIG. [Diagram 3] 2 is a diagram for explaining various positions and various angles used in the light distribution control device according to the first embodiment. FIG. [Figure 4]FIG. 4 is a diagram for explaining calculation of a first angle according to the first embodiment. [Diagram 5] 5 is a flowchart showing the operation of the light distribution control device according to the first embodiment. [Figure 6] 5 is a flowchart showing the operation of the light distribution control device according to the first embodiment. [Figure 7] FIG. 4 is a diagram showing a time chart regarding an inside reference position according to the first embodiment. [Figure 8] FIG. 4 is a diagram for explaining an approach target position according to the first embodiment. [Figure 9] FIG. 4 is a diagram for explaining an approach target position according to the first embodiment. [Figure 10] FIG. 4 is a diagram for explaining an approach target position according to the first embodiment. [Figure 11] 5 is a flowchart showing the operation of the light distribution control device according to the first embodiment. [Figure 12] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 13] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 14] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 15] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 16] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 17] 5 is a diagram illustrating an example of the operation of the light distribution control device according to the first embodiment. FIG. [Figure 18] FIG. 11 is a diagram for explaining an inner reference position according to the second embodiment. [Figure 19] 10 is a flowchart showing the operation of the light distribution control device according to the second embodiment. [Figure 20] 10 is a flowchart showing the operation of the light distribution control device according to the second embodiment. [Figure 21] FIG. 11 is a diagram showing a time chart regarding an inside reference position according to the second embodiment. [Figure 22]FIG. 11 is a diagram showing a time chart regarding an inside reference position according to the second embodiment. [Figure 23] FIG. 11 is a block diagram showing the configuration of a light distribution control device according to a third embodiment. [Figure 24] FIG. 11 is a diagram illustrating an example of the operation of the light distribution control device according to the third embodiment. [Diagram 25] 11 is a flowchart showing the operation of the light distribution control device according to the third embodiment. [Figure 26] FIG. 13 is a block diagram showing the configuration of a light distribution control device according to a fifth embodiment. [Figure 27] 13 is a flowchart showing the operation of the light distribution control device according to the fifth embodiment. [Figure 28] FIG. 13 is a diagram for explaining calculation of an attention position according to the fifth embodiment. [Figure 29] FIG. 13 is a diagram for explaining calculation of an attention position according to the fifth embodiment. [Diagram 30] FIG. 13 is a diagram for explaining various distances according to the fifth embodiment. [Diagram 31] FIG. 13 is a diagram for explaining calculation of a corrected gaze duration according to the fifth embodiment. [Diagram 32] FIG. 13 is a diagram for explaining various positions according to the fifth embodiment. [Diagram 33] FIG. 13 is a diagram for explaining various positions according to the fifth embodiment. [Diagram 34] FIG. 13 is a diagram for explaining various positions according to the fifth embodiment. [Diagram 35] FIG. 13 is a block diagram showing a hardware configuration of a light distribution control device according to another modified example. [Diagram 36] FIG. 13 is a block diagram showing a hardware configuration of a light distribution control device according to another modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <Embodiment 1> First, before describing the light distribution control device according to the present embodiment 1, a general line of sight and driving of a driver when a vehicle enters a curved road will be described. Fig. 1 is a diagram for explaining a general line of sight and driving of a driver when a vehicle enters a curved road.

[0011] <Start of entering curve> The driver visually judges the curvature of the curve based on the angle between the direction to the area FR of the curve where the vehicle will be located in 1-3 seconds and the direction to the inner portion IP of the curve as seen by the driver before entering the curve. To make this judgment, the driver directs his or her gaze toward the area FR and the inner portion IP.

[0012] <Entering a curve> The driver recognizes the vehicle's future driving course by directing his / her gaze to the outer periphery portion OP of the curve while steer- ing the vehicle while gazing at the range FR. In order to determine the curvature at the start of entering the curve and to recognize the driving course while entering the curve, the driver needs to direct his / her gaze to the range FR, the inner periphery portion IP, and the outer periphery portion OP.

[0013] After that, the driver drives the vehicle to turn. Until the vehicle passes the vicinity of the inner circumference part IP, the driver keeps his / her gaze on the inner circumference part IP, and while turning the vehicle based on the inner circumference part IP, he / she keeps his / her gaze on the part of the range FR close to the inner circumference part IP. When the vehicle passes the vicinity of the inner circumference part IP, the driver keeps his / her gaze on the far side of the curve.

[0014] For the above reasons, when a vehicle travels on a curved road, it is preferable that the headlights illuminate the portion of the front of the vehicle close to the inner circumference portion IP and the inner circumference portion IP, and incidentally illuminate the outer circumference portion OP. The light distribution control device according to the present embodiment 1 described below makes such illumination possible.

[0015] Fig. 2 is a block diagram showing the configuration of light distribution control device 12 according to embodiment 1. Fig. 3 is a diagram for explaining various positions and various angles used in light distribution control device 12.

[0016] The light distribution control device 12 in FIG. 2 is mounted on, for example, a vehicle, and is connected to the map information storage unit 1, the position information detection unit 2, the first headlight 10, and the second headlight 11 so as to be able to communicate with each other.

[0017] The map information storage unit 1 stores map information. The map information stored in the map information storage unit 1 may be updated as appropriate with map information from a server. The position information detection unit 2 detects position information indicating the position of the vehicle based on, for example, a signal from a GSNN (Global Navigation Satellite System) satellite.

[0018] The first headlight 10 and the second headlight 11 are headlights of the vehicle. The irradiation direction of the first headlight 10 and the irradiation direction of the second headlight 11 can be controlled separately. In the first embodiment, a third headlight (not shown) capable of emitting low beam is provided on the vehicle, and the first headlight 10 and the second headlight 11 are turned on and off near a curved road. The first headlight 10 and the second headlight 11 may have an ADB (Adaptive Driving Beam) function that can change the shape of the irradiation range of the first headlight 10 and the second headlight 11. The first headlight 10 and the second headlight 11 may also use the function of a high beam headlight having an ADB function.

[0019] The light distribution control device 12 includes an information acquisition unit 3, a driving trajectory estimation unit 4, an inner reference position acquisition unit 5, a proximity target position setting unit 6 which is a target position setting unit, a first angle calculation unit 7, a second angle calculation unit 8, and an illumination control unit 9.

[0020] The information acquisition unit 3 acquires map information from the map information storage unit 1, and acquires location information indicating the location of the vehicle from the location information detection unit 2. As will be described below, the light distribution control device 12 is capable of controlling the light distribution from the vehicle, that is, the light distribution of the first headlight 10 and the second headlight 11, based on the map information and location information acquired by the information acquisition unit 3.

[0021] The traveling locus estimation unit 4 estimates a traveling locus IL of a curved road along which the vehicle 21 will travel in the future, as shown in FIG. 3, based on the map information acquired by the information acquisition unit 3. The traveling locus IL is set, for example, at the center of the road along which the vehicle 21 will travel, among the roads in the map information. The traveling locus IL is represented, for example, by nodes and links following a general data format for roads. In the present embodiment 1, the traveling locus estimation unit 4 estimates the traveling locus IL when the distance between the vehicle 21 indicated by the position information acquired by the information acquisition unit 3 and the curved road in the map information acquired by the information acquisition unit 3 falls within a certain range (for example, 50 m to 100 m).

[0022] The inside reference position acquisition unit 5 acquires the inside reference position. In the present embodiment 1, the inside reference position acquisition unit 5 acquires the inside reference position based on the map information and position information acquired by the information acquisition unit 3. The inside reference position is a position that is associated in advance with the inner periphery of the curve in the map information, and is the position TP or the position ETP in FIG. 3.

[0023] Position TP is the position of the edge of the inner portion of the curve as seen from vehicle 21 located at a predetermined point before the curve. The predetermined point before the curve is, for example, a point 2 to 3 seconds before vehicle 21 enters the curve. If the curve has a white line on the inner side, position TP is a position on the white line.

[0024] Position ETP is a position on a straight line (corresponding to the arrow of direction 24) that passes through vehicle 21, which is located at a predetermined point just before the curve, and end position TP. Position ETP is a position of an intersection between the straight line and the traveling trajectory IL, or a position of an intersection between the straight line and the outer periphery of the curve, and if the curve has a white line on the outer periphery, position ETP is a position on the white line.

[0025] Position TP and position ETP have a one-to-one relationship, and when one of position TP and position ETP is determined, the other is necessarily determined. Therefore, it is sufficient that either position TP or position ETP is determined in the map information, and the inner reference position acquisition unit 5 acquires either position TP or position ETP from the map information as the inner reference position. In the following description, position TP is referred to as inner reference position TP. Furthermore, when position ETP is not distinguished from position TP, it is referred to as inner reference position TP, and when position ETP is distinguished from position TP, it is referred to as inner reference position ETP.

[0026] The proximity target position setting unit 6 sets a proximity target position FP, which is a target position where the vehicle should travel, on the travel path IL, as shown in Fig. 3. In the present embodiment 1, the proximity target position setting unit 6 sets the proximity target position FP on the travel path IL according to a time chart related to the inside reference position TP, which will be described later. The proximity target position FP changes depending on the position of the vehicle 21.

[0027] 3, the first angle calculation unit 7 calculates a first angle θp between a forward direction 22 of the vehicle 21 and a direction 23 from the vehicle 21 to the approach target position FP. The first angle θp changes depending on the position of the vehicle 21.

[0028] 4 is a diagram for explaining the calculation of the first angle θp. The first angle calculation unit 7 calculates the deviation angle between the Y axis and the direction 23 from the vehicle 21 to the proximity target position FP from the position (x(t), y(t)) of the vehicle 21 on the map and the position (x(t+Ti), y(t+Ti)) of the proximity target position FP on the map. Ti is the gaze time, which will be described later.

[0029] The deviation angle θt between the forward direction 22 of the vehicle 21 and the Y axis is calculated, for example, by a steering angle sensor or a yaw rate sensor of the vehicle 21. Therefore, the first angle calculation unit 7 calculates a first angle θp between the forward direction 22 of the vehicle 21 and a direction 23 from the vehicle 21 to the approach target position FP by the following equation (1).

[0030]

number

[0031] 3, the second angle calculation unit 8 calculates a second angle θtp between a forward direction 22 of the vehicle 21 and a direction 24 from the vehicle 21 toward the inner reference position TP. The second angle θtp changes depending on the position of the vehicle 21. The second angle θtp may be calculated in the same manner as the calculation of the first angle θp.

[0032] The irradiation control unit 9 calculates the difference Δθ between the first angle θp and the second angle θtp by the following equation (2).

[0033]

number

[0034] When the difference Δθ is less than the threshold value θth, the illumination control unit 9 controls illumination of the first headlamp 10 of the vehicle 21 based on the proximity target position FP and the inner reference position TP. Through this control, the first headlamp 10 illuminates the proximity target position FP and the inner reference position TP, or the periphery of the proximity target position FP and the inner reference position TP.

[0035] On the other hand, when the difference Δθ is equal to or greater than the threshold value θth, the illumination control unit 9 controls the illumination of the first headlamp 10 based on the proximity target position FP, and controls the illumination of the second headlamp 11 of the vehicle 21 based on the inner reference position TP. Through this control, the first headlamp 10 illuminates the proximity target position FP or its periphery, and the second headlamp 11 illuminates the inner reference position TP or its periphery.

[0036] <Operation> Fig. 5 is a flowchart showing a part of the operation of light distribution control device 12 according to embodiment 1. The operation in Fig. 5 is mainly performed by information acquisition unit 3, driving locus estimation unit 4, inside reference position acquisition unit 5, proximity target position setting unit 6, first angle calculation unit 7, and second angle calculation unit 8.

[0037] 5, the information acquisition unit 3 acquires location information indicating the location of the vehicle in step S1, and then acquires map information in step S2.

[0038] In step S3, the travel trajectory estimation unit 4 determines whether the distance between the vehicle whose position is indicated by the position information in step S1 and the curved road indicated by the map information in step S2 is within a certain range (for example, 50 m to 100 m). If it is determined that the distance is within the certain range, the process proceeds to step S4, and if it is determined that the distance is not within the certain range, the process returns to step S1.

[0039] In step S4, the travel locus estimating unit 4 estimates the travel locus IL based on the map information.

[0040] In step S5, the inside reference position acquisition unit 5 identifies an inner portion of the curve in the map information that is closest to the vehicle position indicated by the position information, based on the map information and the position information acquired by the information acquisition unit 3. Then, the inside reference position acquisition unit 5 acquires an inside reference position TP that is associated in advance with the inner portion of the map information.

[0041] In step S6, the information acquisition unit 3 acquires the vehicle position information at time t. After that, the process proceeds to steps S7 and S8.

[0042] 3 based on the inside reference position TP in step S5, the position information in step S6, and the forward direction 22 of the vehicle 21. Then, the process proceeds to step S31 in FIG.

[0043] In step S8, the proximity target position setting unit 6 acquires vehicle speed information Vs at time t. For example, the proximity target position setting unit 6 may acquire the change in the position information in step S6 per unit time as the vehicle speed information Vs, may acquire the vehicle speed information Vs based on a signal from a vehicle speed sensor (not shown), or may acquire default vehicle speed information Vs.

[0044] In step S9, the proximity target position setting unit 6 sets a proximity target position FP where the vehicle 21 should travel on the travel trajectory IL based on the position information in step S6 and the vehicle speed information Vs in step S8, in accordance with a time chart for the inside reference position TP, which will be described later. The setting of the proximity target position FP will be described in detail later.

[0045] 3 based on the approach target position FP in step S9, the position information in step S6, and the forward direction 22 of the vehicle 21. Then, the process proceeds to step S31 in FIG.

[0046] Fig. 6 is a flow chart showing in detail the setting of the proximity target position FP in step S9. Fig. 7 is a diagram showing a time chart relating to the inside reference position TP used in setting the proximity target position FP.

[0047] 8 is a diagram for explaining the approach target position FP before the vehicle 21 enters a curve, specifically, a diagram for explaining the approach target position FP when the time Ttp [sec] until the vehicle 21 reaches the reference corresponding position CP is less than -3 seconds. A negative time Ttp indicates the time until the vehicle 21 reaches the reference corresponding position CP, and a positive time Ttp indicates the time that has elapsed since the vehicle 21 reached the reference corresponding position CP.

[0048] The reference corresponding position CP in Fig. 8 is a position corresponding to the inner reference position TP on the travel path IL. In the present embodiment 1, the reference corresponding position CP is the position of the intersection between a straight line extending from the inner reference position TP in the width direction of the curve and the travel path IL. Note that the distances Ltp and Lfp are distances on the travel path IL, but are shifted in Fig. 8 for convenience. This also applies to the figures subsequent to Fig. 8.

[0049] In step S21 in Fig. 6, the proximity target position setting unit 6 sets the reference corresponding position CP in Fig. 8 based on the inner reference position TP. Then, the proximity target position setting unit 6 calculates the distance Ltp (see Fig. 8) between the vehicle 21 and the reference corresponding position CP based on the position of the vehicle 21 indicated by the position information and the reference corresponding position CP. Note that various distances such as the distance Ltp can be calculated based on an integrated value of the link lengths of the map information.

[0050] In step S22, the approach target position setting unit 6 calculates the time Ttp required for the vehicle 21 to reach the reference corresponding position CP by applying the vehicle speed information Vs in step S8 of FIG. 5 and the distance Ltp in step S21 to the following equation (3).

[0051]

number

[0052] In step S23, the proximity target position setting unit 6 acquires the gaze time Ti corresponding to the time Ttp in step S22 from the time chart which is a graph in Fig. 7. Note that the horizontal axis of the time chart in Fig. 7 is the time Ttp, and the vertical axis is the gaze time Ti.

[0053] In step S24, the proximity target position setting unit 6 calculates the distance Lfp in FIG. 8 between the vehicle 21 and the proximity target position FP by applying the vehicle speed information Vs in step S8 in FIG. 5 and the gaze time Ti in step S23 to the following equation (4).

[0054]

number

[0055] In step S25, the proximity target position setting unit 6 sets the proximity target position FP at a position distance Lfp away along the travel trajectory IL from the vehicle 21. After that, the operation in Fig. 6, that is, the process in step S9 in Fig. 5, ends.

[0056] Next, the change in the approach target position FP will be described. Fig. 8 shows the approach target position FP when the time Ttp required for the vehicle 21 to reach the reference corresponding position CP is shorter than -3 seconds. In the time chart of Fig. 7, a fixed gaze time Ti (for example, 2.5 seconds, i.e., the time indicated by the arrow in the figure) is associated with a time Ttp shorter than -3 seconds.

[0057] Fig. 9 is a diagram for explaining the approach target position FP before the vehicle 21 enters a curved road, specifically, a diagram for explaining the approach target position FP when the time Ttp is -3 seconds or more and less than -1 second. In the time chart of Fig. 7, the time Ttp that is -3 seconds or more and less than -1 second is associated with a gaze time Ti that is less than or equal to the time Ttp, and the gaze time Ti becomes shorter as the time Ttp becomes longer. Therefore, in the period of Fig. 9, the distance Lfp between the vehicle 21 and the approach target position FP becomes smaller.

[0058] Fig. 10 is a diagram for explaining the approach target position FP before the vehicle 21 enters the reference corresponding position CP, specifically, a diagram for explaining the approach target position FP when the time Ttp is -1 second. In the time chart of Fig. 7, the time Ttp of -1 second is associated with the gaze time Ti of 1 second. Therefore, at the time of Fig. 10, the approach target position FP and the reference corresponding position CP overlap.

[0059] For the above reasons, in the present embodiment 1, before the vehicle 21 reaches the reference corresponding position CP, the proximity target position setting unit 6 is configured to reduce the distance Lfp between the proximity target position FP and the vehicle 21. Therefore, before the vehicle 21 reaches the reference corresponding position CP, the proximity target position FP is set generally on the vehicle 21 side with respect to the reference corresponding position CP.

[0060] 7, a fixed (e.g., 1 second) gaze time Ti is associated with a time Ttp that is equal to or greater than -1 second and smaller than 0 second. Therefore, during this period, the approach target position FP is set on the opposite side of the vehicle 21 with respect to the reference corresponding position CP.

[0061] In the time chart of Fig. 7, the time Ttp that is 0 seconds or more is associated with a gaze time Ti such that the longer the time Ttp, the longer the gaze time Ti becomes. Therefore, during this period, if the vehicle speed information Vs is constant, the distance Lfp between the vehicle 21 and the proximity target position FP becomes longer. In other words, in the first embodiment, the proximity target position setting unit 6 is configured to increase the distance Lfp between the proximity target position FP and the vehicle 21 as the vehicle 21 moves away beyond the reference corresponding position CP.

[0062] 11 is a flowchart showing the operation of the remaining parts of light distribution control device 12 according to embodiment 1. The operation in FIG.

[0063] In step S31, the irradiation control unit 9 calculates the difference Δθ between the second angle θtp calculated in step S7 of FIG. 5 and the first angle θp calculated in step S10 of FIG. 5 by using the above-mentioned formula (2).

[0064] In step S32, the irradiation control unit 9 determines whether the difference Δθ in step S31 is less than the threshold θth. If it is determined that the difference Δθ is less than the threshold θth, the process proceeds to step S33, and if it is determined that the difference Δθ is equal to or greater than the threshold θth, the process proceeds to step S34.

[0065] In step S33, the illumination control unit 9 controls the illumination of the first headlamp 10 based on the proximity target position FP and the inner reference position TP. As a result, the first headlamp 10 illuminates the proximity target position FP and the inner reference position TP. Then, the process proceeds to step S35.

[0066] In step S34, the illumination control unit 9 controls illumination of the first headlamp 10 based on the proximity target position FP, and controls illumination of the second headlamp 11 based on the inside reference position TP. As a result, the first headlamp 10 illuminates the proximity target position FP, and the second headlamp 11 illuminates the inside reference position TP. Then, the process proceeds to step S35.

[0067] In step S35, the illumination control unit 9 determines whether or not the vehicle 21 has passed the reference corresponding position CP. If it is determined that the vehicle 21 has passed the reference corresponding position CP, the process proceeds to step S36, and if it is determined that the vehicle 21 has not passed the reference corresponding position CP, the process returns to step S6 in FIG.

[0068] In step S36, the illumination control unit 9 turns off the second headlamp 11.

[0069] In step S37, the illumination control unit 9 judges whether the vehicle 21 is traveling on a straight road that is not a curved road. Whether the vehicle is traveling on a straight road may be judged by whether the first angle θp is continuously equal to or smaller than a threshold value every time the vehicle travels a certain distance, or may be judged based on the position information and the map information. If it is judged that the vehicle is traveling on a straight road, the process proceeds to step S38, and if it is judged that the vehicle is not traveling on a straight road, the process proceeds to step S39.

[0070] In step S38, the illumination control unit 9 turns off the first headlamp 10. Then, the operation in Fig. 11 ends. After that, the operation in Fig. 5 is started as appropriate.

[0071] In step S39, after the same processes as in steps S6, S8, and S9 are performed, the illumination control unit 9 controls the illumination of the first headlight 10 based on the proximity target position FP. As a result, the first headlight 10 illuminates the proximity target position FP. Then, the process returns to step S37. Note that if another curve is detected during the loop process of steps S38 and S39, the process may return to step S4.

[0072] Each of Fig. 12 to Fig. 15 is a diagram showing an example of the operation of the light distribution control device 12 according to the first embodiment. In any of the states shown in Fig. 12 to Fig. 15, a low beam is emitted from the vehicle 21, and the illumination range of the low beam is indicated by a dashed line. Fig. 12 to Fig. 15 also show an illumination range 10a of the first headlight 10 and an illumination range 11a of the second headlight 11.

[0073] 12 and 13 show the operation of the light distribution control device 12 before the vehicle 21 enters a curved road, and the state of FIG. 13 is a state after the state of FIG. 12. In the state of FIG. 12, the light distribution control device 12 sets a proximity target position FP on a straight portion of the travel locus IL and acquires an inner reference position TP. In the state of FIG. 12, the light distribution control device 12 controls the illumination of the first headlight 10 based on the proximity target position FP and the inner reference position TP. In the state of FIG. 12, the proximity target position FP and the inner reference position TP are illuminated by the first headlight 10, and in the state of FIG. 13, the proximity target position FP, the inner reference position TP, and the inner reference position ETP are illuminated by the first headlight 10. Note that the distance between the vehicle 21 and the proximity target position FP becomes small for a while from the state of FIG. 12.

[0074] Fig. 14 shows the operation of the light distribution control device 12 before the vehicle 21 enters the reference corresponding position CP. In the state of Fig. 14, the difference Δθ becomes equal to or greater than the threshold value θth, and the light distribution control device 12 controls the illumination of the first headlight 10 based on the proximity target position FP, and controls the illumination of the second headlight 11 based on the inner reference position TP. The illuminance of the second headlight 11 may be higher than the illuminance of the first headlight 10. The illuminance corresponds to luminous intensity or brightness.

[0075] Fig. 15 shows the operation of the light distribution control device 12 when the vehicle 21 passes the reference corresponding position CP. In the state of Fig. 15, the light distribution control device 12 controls the illumination of the first headlamp 10 based on the proximity target position FP, and turns off the second headlamp 11.

[0076] Fig. 16 and Fig. 17 are diagrams showing an example of the operation of the light distribution control device 12 according to the first embodiment when a first curve, a second curve, and a third curve are consecutive. In Fig. 16 and Fig. 17, the illumination range of the low beam is omitted. The arrow (1) indicates the line of sight from the driver to the approach target position FP, the arrow (2) indicates the line of sight from the driver to the inner reference position TP, and the arrow (3) indicates the line of sight to the future position, which is a position of the vehicle 21 farther than the approach target position FP. The future position is, for example, the position of the vehicle 21 five seconds later.

[0077] FIG. 16(a) shows a state three seconds before the vehicle 21 enters the first curve, and the approach target position FP and the inside reference position TP of the first curve are generally illuminated by the first headlamp 10.

[0078] Figure 16 (b) shows the state 2 seconds before the vehicle 21 enters the first curve, and the approach target position FP, the inside reference position TP and the inside reference position ETP of the first curve, and the future position are generally illuminated by the first headlamp 10.

[0079] Figure 16(c) shows the state one second before the vehicle 21 enters the first curve, with the approach target position FP and future position being roughly illuminated by the first headlight 10, and the inside reference position TP of the first curve being roughly illuminated by the second headlight 11.

[0080] 17(a) shows a state three seconds before the vehicle 21 enters the second curve, and the approach target position FP, the inside reference position TP and the inside reference position ETP of the second curve, and the future position are generally illuminated by the first headlight 10. The second headlight 11 is turned off.

[0081] Figure 17(b) shows the state one second before the vehicle 21 enters the second curve, with the approach target position FP and future position being roughly illuminated by the first headlight 10, and the inner reference position TP of the second curve being roughly illuminated by the second headlight 11.

[0082] 17(c) shows a state three seconds before the vehicle 21 enters the third curve, and the approach target position FP, the inside reference position TP and the inside reference position ETP of the third curve, and the future position are generally illuminated by the first headlight 10. The second headlight 11 is turned off.

[0083] Figure 17(d) shows the state one second before the vehicle 21 enters the third curve, with the approach target position FP and future position being roughly illuminated by the first headlight 10, and the inside reference position TP of the third curve being roughly illuminated by the second headlight 11.

[0084] Although not described above, the curved road may include a bent portion such as an intersection or a T-junction. The first headlight 10 may have an ADB function to form a light distribution pattern capable of illuminating the outside of the left or right end of the low beam illumination range. Furthermore, the first headlight 10 may utilize the function of a high beam headlight having an ADB function. With such a configuration, the illumination distance and illumination width (directional angle) can be freely changed, so that appropriate illumination can be performed. The first headlight 10 may also be capable of depression angle control.

[0085] <Summary of the first embodiment> According to the light distribution control device 12 of the first embodiment as described above, when the difference Δθ is less than the threshold value θth, the illumination of the first headlamp 10 of the vehicle 21 is controlled based on the proximity target position FP and the inner reference position TP. When the difference Δθ is equal to or greater than the threshold value θth, the illumination of the first headlamp 10 is controlled based on the proximity target position FP, and the illumination of the second headlamp 11 of the vehicle 21 is controlled based on the inner reference position TP. According to this configuration, when the vehicle 21 travels on a curved road, not only is the proximity target position FP illuminated, but the time during which the inner reference position TP is illuminated is also extended. Therefore, the proximity target position FP and the inner reference position TP, which are the references for the driver's driving plan on a curved road, can be illuminated appropriately, and therefore the driving of the driver on a curved road can be appropriately assisted.

[0086] In the first embodiment, the inner reference position is the position TP of the end of the inner circumference portion, or the position ETP on the straight line passing through the vehicle 21 and the end. With this configuration, the inner reference position is fixed, so that the illumination direction is stable even on a sharp curved road with a certain curvature or more, and therefore it is possible to appropriately assist the driver in driving on a curved road.

[0087] In the first embodiment, the position ETP is the intersection of a straight line passing through the vehicle 21 and the position TP and the travel path IL, or the intersection of the straight line and the outer periphery of the curve. With this configuration, when the vehicle 21 has traveled a certain distance around the curve, the driver can easily confirm the position ETP, which is near the exit of the curve.

[0088] Moreover, in the first embodiment, before the vehicle 21 reaches the reference corresponding position CP, the distance between the approach target position FP and the vehicle 21 is reduced. With this configuration, the approach target position FP can be set near the inside reference position TP that the driver should be aware of when driving around a sharp curve or the like.

[0089] Furthermore, in the first embodiment, as the vehicle 21 moves away beyond the reference corresponding position CP, the distance between the proximity target position FP and the vehicle 21 is increased. With this configuration, it is possible to set the proximity target position FP that matches the tendency of the driver's attention to be gradually directed away until the vehicle 21 moves beyond the reference corresponding position CP and exits the curved road.

[0090] <Embodiment 2> A block diagram showing the configuration of light distribution control device 12 according to the second embodiment is similar to the block diagram in Fig. 2. Hereinafter, among the components according to the second embodiment, components that are the same as or similar to the components described above are given the same or similar reference symbols, and different components will be mainly described.

[0091] Fig. 18 is a diagram for explaining the inside reference position according to the second embodiment. In the first embodiment, one inside reference position TP is associated in advance with the inner periphery of one curve. In contrast to this, in the second embodiment, a plurality of inside reference positions TP are associated in advance with one curve. In Fig. 18, as an example, a first inside reference position TP1 and a second inside reference position TP2 are associated in advance with the inner periphery of one curve as the inside reference positions TP. Note that the second inside reference position TP2 is farther away from the vehicle 21 than the first inside reference position TP1.

[0092] The proximity target position setting unit 6 performs the same operation as for the inner reference position TP for the first inner reference position TP1 and the second inner reference position TP2. As a result, the proximity target position setting unit 6 sets the first proximity target position FP1, which is the proximity target position FP, based on the first inner reference position TP1, and sets the second proximity target position FP2, which is the proximity target position FP, based on the second inner reference position TP2.

[0093] The irradiation control unit 9 calculates the distance Δf between the first proximity target position FP1 and the second proximity target position FP2 by applying the distance Lfp2, which is the distance Lfp of the second proximity target position FP2, and the distance Lfp1, which is the distance Lfp of the first proximity target position FP1, to the following equation (5).

[0094]

number

[0095] The irradiation control unit 9 determines whether or not the distance Δf between the first proximity target position FP1 and the second proximity target position FP2 is equal to or greater than a threshold value Fth. In the following, for simplicity, the threshold value Fth is assumed to be 0.

[0096] When it is determined that the distance Δf is equal to or greater than the threshold value Fth, the illumination control unit 9 controls the first headlamp 10 based on each of the first proximity target position FP1 and the second proximity target position FP2, similar to the first embodiment. That is, after the change of the gaze time Ti for calculating the first proximity target position FP1 is completed, the illumination control unit 9 changes the gaze time Ti for calculating the second proximity target position FP2 from the default time.

[0097] On the other hand, when it is determined that the distance Δf is less than the threshold value Fth, the illumination control unit 9 changes the gaze time Ti for calculating the second proximity target position FP2 midway before the change of the gaze time Ti for calculating the first proximity target position FP1 is completed. This will be described in detail later.

[0098] <Operation> Fig. 19 and Fig. 20 are flowcharts showing the operation of light distribution control device 12 according to embodiment 2. Note that, since the processing of steps S1 to S4, and S6 in Fig. 19 is similar to the processing of steps S1 to S4, and S6 in Fig. 5, detailed description of the processing will be omitted as appropriate.

[0099] After step S4, step S5a is performed. In step S5a, the inner reference position acquisition unit 5 acquires the first inner reference position TP1 and the second inner reference position TP2 in the same manner as the acquisition of the inner reference position TP in step S5 of Fig. 5. Then, the process proceeds to step S6.

[0100] In step S6, the information acquisition unit 3 acquires the position information of the vehicle at time t.

[0101] After that, in step S41, the same processes as steps S7 to S10 in Fig. 5 and step S31 in Fig. 11 are performed for the first inner reference position TP1. As a result, first parameters including the first angle θp1, the second angle θtp1, the first gaze time Ti1, the first proximity target position FP1, the first reference corresponding position CP1, and the difference Δθ1 are acquired. In other words, the first parameters include the first angle θp, the second angle θtp, the gaze time Ti, the proximity target position FP, the reference corresponding position CP, and the difference Δθ regarding the first inner reference position TP1.

[0102] In step S42, the irradiation control unit 9 performs the same processes as steps S32 to S34 in Fig. 11 based on the first parameter in step S41. As a result, for the first inner reference position TP1, light distribution control similar to the light distribution control for the inner reference position TP described in the first embodiment is performed.

[0103] In step S43, for the second inner reference position TP2, the same processes as those in steps S8 and S9 in Fig. 5 are performed. As a result, the second proximity target position FP2, which is the proximity target position FP of the second inner reference position TP2, is acquired.

[0104] In step S44, the irradiation control unit 9 calculates the distance Δf between the first proximity target position FP1 included in the first parameter in step S41 and the second proximity target position FP2 in step S43 by using the above-mentioned formula (5).

[0105] 20, the irradiation control unit 9 determines whether the distance Δf is equal to or greater than the threshold value Fth. If it is determined that the distance Δf is equal to or greater than the threshold value Fth, the process proceeds to step S46, and if it is determined that the distance Δf is less than the threshold value Fth, the process proceeds to step S53.

[0106] In step S46, the illumination control unit 9 determines whether or not the vehicle 21 has passed the first reference corresponding position CP1. If it is determined that the vehicle 21 has passed the first reference corresponding position CP1, the process proceeds to step S47. If it is determined that the vehicle 21 has not passed the first reference corresponding position CP1, the process returns to step S6 in Fig. 19, and the light distribution control for the first inner reference position TP1 is continued.

[0107] In step S47, the illumination control unit 9 turns off the second headlamp 11.

[0108] In step S48, the illumination control unit 9 judges whether or not the vehicle 21 is traveling on a straight road that is not a curved road. If it is judged that the vehicle 21 is traveling on a straight road, the process proceeds to step S49. If it is judged that the vehicle 21 is not traveling on a straight road, the same process as step S39 in Fig. 11 is performed, and then the process returns to step S45, and the light distribution control for the first inner reference position TP1 is continued.

[0109] In step S49, the illumination control unit 9 turns off the first headlamp 10. When the process of step S49 is completed, the light distribution control for the first inner reference position TP1 is completed.

[0110] In step S50, the same processing as in steps S6 and S41 is performed for the second inner reference position TP2. This results in acquisition of second parameters including the first angle θp2, the second angle θtp2, the second gaze time Ti2, the second proximity target position FP2, the second reference corresponding position CP2, and the difference Δθ2. In other words, the second parameters are the first angle θp, the second angle θtp, the gaze time Ti, the proximity target position FP, the reference corresponding position CP, and the difference Δθ for the second inner reference position TP2.

[0111] In step S51, the irradiation control unit 9 performs the same processes as steps S32 to S34 in Fig. 11 based on the second parameter in step S50. As a result, for the second inner reference position TP2, light distribution control similar to the light distribution control for the inner reference position TP described in the first embodiment is performed.

[0112] In step S52, the illumination control unit 9 determines whether or not the vehicle 21 has passed the second reference corresponding position CP2. If it is determined that the vehicle 21 has passed the second reference corresponding position CP2, the process proceeds to step S56. If it is determined that the vehicle 21 has not passed the second reference corresponding position CP2, the process returns to step S50, and the light distribution control for the second inner reference position TP2 is continued.

[0113] In step S53, the illumination control unit 9 ends the light distribution control for the first inner reference position TP1 midway, although the change of the first gaze time Ti1 for calculating the first proximity target position FP1 has not been completed.

[0114] In step S54, the same processing as in steps S50 and S51 is performed. As a result, the second parameter is acquired, and light distribution control is performed for the second inner reference position TP2. Note that, in order to perform light distribution control for the second inner reference position TP2 as early as possible, the processing to acquire the second parameter may be performed before step S54.

[0115] In step S55, it is determined whether or not the vehicle 21 has passed the second reference corresponding position CP2. If it is determined that the vehicle 21 has passed the second reference corresponding position CP2, the process proceeds to step S56. If it is determined that the vehicle 21 has not passed the second reference corresponding position CP2, the process returns to step S54, and the light distribution control for the second inner reference position TP2 is continued.

[0116] In step S56, the same processes as steps S36 to S39 in Fig. 11 are performed for the second inner reference position TP2. When the process of step S56 is completed, the light distribution control for the second inner reference position TP2 is completed, and the operation in Fig. 19 ends. After this, the operation in Fig. 19 is started as appropriate.

[0117] Fig. 21 is a time chart when the distance Δf is equal to or greater than the threshold value Fth. The time chart in Fig. 21 corresponds to the time chart in Fig. 7 for the first inner reference position and the time chart in Fig. 7 for the second inner reference position arranged side by side. In the time chart in Fig. 21, after the change of the first gaze time Ti1 for setting the first proximity target position FP1 is completed, the second gaze time Ti2 for setting the second proximity target position FP2 is changed from the default time.

[0118] Fig. 22 is a time chart when the distance Δf is less than the threshold value Fth. The time chart in Fig. 22 corresponds to a time chart in which the time chart in Fig. 7 for the first inner reference position and the time chart in Fig. 7 for the second inner reference position are partially overlapped. In the time chart in Fig. 22, the second gaze time Ti2 for setting the second proximity target position FP2 changes from the same time as the first gaze time Ti1 before the change of the first gaze time Ti1 for setting the first proximity target position FP1 is completed.

[0119] 22 as well as in Fig. 21, the first proximity target position FP1 and the second proximity target position FP2 substantially overlap at the time of switching from light distribution control based on the first inner reference position TP1 to light distribution control based on the second inner reference position TP2. Therefore, switching from the first proximity target position FP1 to the second proximity target position FP2 can be performed smoothly regardless of the distance between the first inner reference position TP1 and the second inner reference position TP2.

[0120] <Summary of the second embodiment> If the first proximity target position FP1 is switched to the second proximity target position FP2, which is significantly different from the first proximity target position FP1, due to the switching to the light distribution control, the driver may feel uncomfortable and confused. In contrast, according to the second embodiment, when it is determined that the distance Δf is less than the threshold value Fth, the second gaze time Ti2 is changed from the same time as the first gaze time Ti1 before the change of the first gaze time Ti1 is completed. With this configuration, the first proximity target position FP1 can be smoothly switched to the second proximity target position FP2, so that the possibility of the driver feeling uncomfortable and confused can be reduced.

[0121] <Embodiment 3> 23 is a block diagram showing the configuration of light distribution control device 12 according to embodiment 3. Below, among the components according to embodiment 3, components that are the same as or similar to the components described above are given the same or similar reference symbols, and different components will be mainly described.

[0122] 23 is communicatively connected to a monitoring device 13. The monitoring device 13 includes a monitoring camera 14 provided in a vehicle cabin. The monitoring camera 14 generates image information including the face of the driver and outputs the image information to the light distribution control device 12.

[0123] The light distribution control device 12 in Fig. 23 has the same configuration as the light distribution control device 12 in Fig. 2, with an attention direction estimation unit 15 added. The attention direction estimation unit 15 estimates the attention direction, which is the direction in which the driver is paying attention. In this embodiment 3, the attention direction estimation unit 15 extracts the line of sight or face direction of the driver from the output of the surveillance camera 14, i.e., the image information generated by the surveillance camera 14, and estimates the attention direction based on the line of sight or face direction. The attention direction according to this embodiment 3 is represented by a left / right angle based on the forward direction of the vehicle, and will be referred to as attention direction θdr below.

[0124] The illumination control unit 9 increases the illuminance of the attention range, which is a range corresponding to the attention direction θdr, out of the illumination range 10a of the first headlight 10 and the illumination range 11a of the second headlight 11.

[0125] Fig. 24 is a diagram showing an example of the operation of the light distribution control device 12 according to the embodiment 3. Fig. 24 shows a case where an attention range 26 corresponding to the attention direction θdr is included in the illumination range 10a of the first headlight 10. The attention range 26 may be a part of the illumination range 10a as shown in Fig. 24(a), or may be the entire illumination range 10a as shown in Fig. 24(b).

[0126] The above also applies to the case where the attention area is included in the illumination range 11a of the second headlight 11. Illumination as shown in Fig. 24(a) is preferably used when the attention area is included in the illumination range 10a of the first headlight 10, and illumination as shown in Fig. 24(b) is preferably used when the attention area is included in the illumination range 11a of the second headlight 11.

[0127] 24(a) that defines the width of the attention range 26 may be arbitrarily set by, for example, the driver. In addition, the narrow directivity angle θnt that defines the width of the attention range 26 included in the illumination range 10a may be different from the narrow directivity angle θnt that defines the width of the attention range 26 included in the illumination range 11a.

[0128] 25 is a flowchart showing the operation of the light distribution control device 12 according to the embodiment 3. This operation is performed until both the first headlight 10 and the second headlight 11 are turned off.

[0129] In step S61, the attention direction estimation unit 15 acquires image information generated by the monitoring camera 14 of the monitoring device 13.

[0130] In step S62, the attention direction estimating unit 15 estimates the driver's attention direction θdr based on the image information in step S61.

[0131] In step S63, the illumination control unit 9 determines whether or not the attention range 26 corresponding to the attention direction θdr in step S62 is included within the illumination range 10a of the first headlight 10 and the illumination range 11a of the second headlight 11. If it is determined that the attention range 26 is included within the illumination ranges 10a, 11a, the process proceeds to step S64, and if it is determined that the attention range 26 is not included within the illumination ranges 10a, 11a, the process returns to step S61.

[0132] In step S64, the illumination control unit 9 increases the illuminance of the illumination range 10a of the first headlight 10 and the attention range 26 in the illumination range 11a of the second headlight 11. After that, the process returns to step S61.

[0133] <Summary of the Third Embodiment> The light distribution control device 12 according to the third embodiment described above increases the illuminance in the range corresponding to the attention direction θdr among the illumination range 10a of the first headlight 10 and the illumination range 11a of the second headlight 11. With this configuration, it is possible to increase the illuminance in the range to which the driver is paying attention, thereby appropriately assisting the driver in driving on a curved road.

[0134] The illumination control unit 9 may increase the luminance of the attention range 26 only when the difference between the first angle θp or the second angle θtp and the driver's attention direction θdr is within a threshold value (e.g., 5 degrees). With this configuration, it is possible to suppress a sudden change in illuminance in the illumination ranges 10a, 11a when the driver directs his or her gaze in a direction other than the proximity target position FP and the inner reference position TP.

[0135] <Fourth embodiment> A block diagram showing the configuration of light distribution control device 12 according to this embodiment 4 is similar to the block diagram in Fig. 23. Hereinafter, among the components according to this embodiment 4, components that are the same as or similar to the components described above will be given the same or similar reference symbols, and different components will be mainly described.

[0136] In the third embodiment, the attention direction estimation unit 15 estimates the attention direction θdr based on the output of the surveillance camera 14 in the vehicle. In the fourth embodiment, the attention direction estimation unit 15 estimates the attention direction θdr based on the output of a steering angle sensor (not shown) of the vehicle in addition to this estimation. Hereinafter, the attention direction θdr based on the output of the surveillance camera 14 is referred to as the first attention direction θdr1, and the attention direction θdr based on the output of the steering angle sensor is referred to as the second attention direction θdr2.

[0137] When the first attention direction θdr1 and the second attention direction θdr2 are obtained, the illumination control unit 9 uses the second attention direction θdr2 preferentially over the first attention direction θdr1. For example, when the first attention direction θdr1 and the second attention direction θdr2 are obtained, the illumination control unit 9 increases the illuminance of the range corresponding to the second attention direction θdr2 among the illumination range 10a and the illumination range 11a, regardless of the first attention direction θdr1.

[0138] The second attention direction θdr2 generally corresponds to the travel path IL in FIG. 3, but is more accurate than the travel path IL obtained by estimation. Generally, the second attention direction θdr2 is more accurate than the first attention direction θdr1. Therefore, by using the second attention direction θdr2 with priority, the accuracy of the range in which the driver is paying attention can be improved.

[0139] In actual operation, it is assumed that only one of the first attention direction θdr1 and the second attention direction θdr2 can be obtained for some reason. In such a case, the illumination control unit 9 may increase the illuminance of the range corresponding to the one of the attention directions among the illumination range 10a of the first headlight 10 and the illumination range 11a of the second headlight 11.

[0140] <Summary of the fourth embodiment> According to the light distribution control device 12 of the fourth embodiment as described above, when the first attention direction θdr1 and the second attention direction θdr2 are obtained, the illumination control unit 9 uses the second attention direction θdr2 with priority over the first attention direction θdr1. This makes it possible to improve the accuracy of the range in which the driver is paying attention, thereby appropriately assisting the driver in driving on a curved road.

[0141] <Embodiment 5> Fig. 26 is a block diagram showing the configuration of light distribution control device 12 according to embodiment 4. Below, among the components according to embodiment 4, components that are the same as or similar to the components described above are given the same or similar reference symbols, and different components will be mainly described.

[0142] The light distribution control device 12 in FIG. 26 has a similar configuration to the light distribution control device 12 in FIG. 23 with a correction unit 16 added.

[0143] The attention direction estimation unit 15 estimates the attention direction, which is the direction in which the driver is paying attention, in the same manner as in the third embodiment. However, the attention direction in the fifth embodiment is represented by an angle above and below the horizontal direction, that is, an elevation / depression angle, and is hereinafter referred to as the attention direction θd.

[0144] The correction unit 16 performs correction based on the attention direction θd so as to bring the approach target position FP closer to the attention position FPd, which is a position corresponding to the attention direction θd.

[0145] 27 is a flowchart showing the operation of light distribution control device 12 according to embodiment 5. This operation is performed in parallel with the operation in FIG.

[0146] In step S71, the attention direction estimation unit 15 acquires image information generated by the monitoring camera 14 of the monitoring device 13.

[0147] In step S72, the attention direction estimation unit 15 estimates the driver's attention direction θd based on the image information in step S71, and also estimates the height of the driver's head or line of sight.

[0148] In step S73, the correction unit 16 sets an attention position FPd, which is a position corresponding to the attention direction θd, based on the attention direction θd, the height of the driver's head or line of sight, the elevation difference shown in the map information, the position information of the vehicle 21, and the traveling trajectory IL. Note that the position information of the vehicle 21 used to set the attention position FPd is acquired during the processing of steps S71 and S72.

[0149] Fig. 28 is a diagram for explaining the setting of the attention position in step S73. The upper diagram in Fig. 28 is a cross-sectional view, and the lower diagram in Fig. 28 is a plan view.

[0150] As shown in Fig. 28, the correction unit 16 calculates the distance Ld for setting the attention position FPd by applying the attention direction θd, the height h of the head or line of sight of the driver 31, and the height difference Δh to the following equation (6). It is clear from the upper diagram of Fig. 28 that the following equation (6) holds true.

[0151]

number

[0152] Based on the position information of the vehicle 21, the driving trajectory IL, and the distance Ld, the correction unit 16 sets the intersection of the driving trajectory IL and an arc-shaped candidate position 32 that is the distance Ld away from the position of the vehicle 21 as the attention position FPd, as shown in the lower diagram of Figure 28.

[0153] Fig. 29 is a diagram for explaining setting of the attention position FPd based on the position information of the vehicle 21, the travel path IL, and the distance Ld. In Fig. 29, the dashed ellipse is shown in an enlarged manner, and within the dashed ellipse, nodes Ln1 to Ln4 that define the travel path IL are shown.

[0154] In the state of FIG. 29, the correction unit 16 may set the node Ln2, which is the closest to the intersection of the candidate position 32 and the traveling trajectory IL, among the nodes Ln1 to Ln4, as the attention position FPd. With this configuration, it is possible to use existing coordinates without defining new coordinates, and therefore it is possible to suppress an increase in the amount of information. The correction unit 16 may set the node Ln2, which is the closest to the intersection of the candidate position 32 and the traveling trajectory IL, the node Ln3, which is the second closest, and the ratio between them as the attention position FPd. With this configuration, it is possible to improve the accuracy of the attention position FPd.

[0155] 27, the correction unit 16 acquires the proximity target position FP set by the proximity target position setting unit 6. The correction unit 16 also acquires the vehicle speed information Vs and the time Ttp required for the vehicle 21 to reach the reference corresponding position CP, which was acquired by the proximity target position setting unit 6 in step S22 of FIG. 6 when the proximity target position setting unit 6 set the proximity target position FP.

[0156] In step S75, the correction unit 16 calculates a distance ΔLds between the attention position FPd and the proximity target position FP on the travel path IL based on the attention position FPd in ​​step S73 and the proximity target position FP in step S74. Fig. 30 is a diagram showing the distance ΔLds and the distance Ltp corresponding to the time Ttp. In the following description, when ΔLds is positive, it indicates that the attention position FPd is located farther away from the vehicle 21 than the proximity target position FP.

[0157] The correction unit 16 calculates the time ΔTds corresponding to the distance ΔLds by applying the vehicle speed information Vs in step S74 and the distance ΔLds to the following equation (7). As will be described next, the time ΔTds is used as a correction amount.

[0158]

number

[0159] In step S76, the correction unit 16 obtains the gaze time Ti corresponding to the time Ttp in step S74 from the time chart in Fig. 7. Then, the correction unit 16 applies the gaze time Ti and the time ΔTds in step S75 to the following equation (8) to calculate the corrected gaze time Tic.

[0160]

number

[0161] Fig. 31 is a diagram for explaining the gaze time Tic after correction in step S76. Fig. 31 shows a pre-correction time chart Ts showing the relationship between the gaze time Ti before correction and the time Ttp, and a post-correction time chart Td showing the relationship between the gaze time Tic after correction and the time Ttp. In the example of Fig. 31, a case is shown in which the time ΔTds is a positive value and the attention position FPd is farther away from the vehicle 21 than the approach target position FP before correction. In addition, in the example of Fig. 31, different values ​​of time ΔTds are calculated for the time Ttp before -3 seconds, the time Ttp from -3 seconds to -1 second, and the time Ttp after 0 seconds.

[0162] 27, the proximity target position setting unit 6 applies the corrected gaze time Tic instead of the gaze time Ti to the above-mentioned formula (4) to set the corrected proximity target position FP. Then, the process returns to step S71.

[0163] Figures 32, 33 and 34 are diagrams showing the attention position FPd, the proximity target position FP before correction, and the proximity target position FP after correction. In Figures 32 to 34, the proximity target position FP before correction is shown by a white circle, and the proximity target position FP after correction is shown by a black square. As shown in Figures 32 to 34, the proximity target position FP after correction is closer to the attention position FPd than the proximity target position FP before correction.

[0164] In Fig. 32, the gaze time Ti before correction and the gaze time Tic after correction are 2.5 seconds and 2.8 seconds, respectively, and the correction amount of time ΔTds is 0.3 seconds. In Fig. 33, the gaze time Ti before correction and the gaze time Tic after correction are 1.2 seconds and 1.4 seconds, respectively, and the correction amount of time ΔTds is 0.2 seconds. In Fig. 34, the gaze time Ti before correction and the gaze time Tic after correction are 1 second and 1.1 seconds, respectively, and the correction amount of time ΔTds is 0.1 seconds.

[0165] <Summary of the fifth embodiment> According to the light distribution control device 12 of the fifth embodiment as described above, a correction is performed to move the proximity target position FP closer to the attention position FPd corresponding to the attention direction θd, based on the attention direction θd. With such a configuration, it is possible to realize light distribution control that matches the line of sight characteristics and driving characteristics unique to the driver 31.

[0166] In the above description, the time chart in Fig. 31 is corrected in real time, but a corrected time chart suitable for the driving characteristics of an authenticated driver may be learned, created, stored, and applied in advance using technologies such as driver authentication and machine learning functions. Also, although the system becomes larger, a corrected time chart may be learned, created, stored, and applied in advance for each curve.

[0167] Moreover, instead of directly using the time ΔTds, which is the correction amount calculated by the formula (7), in the formula (8), upper and lower thresholds may be set for the time ΔTds to limit the correction amount within a certain range. With such a configuration, it is possible to prevent the post-correction time chart from deviating significantly from the pre-correction time chart. Also, it becomes easy to control the distance Lfp between the approach target position FP and the vehicle 21 to be reduced before the vehicle 21 reaches the reference corresponding position CP, as described in the first embodiment.

[0168] <Other Modifications> The information acquisition unit 3, the traveling trajectory estimation unit 4, the inside reference position acquisition unit 5, the proximity target position setting unit 6, the first angle calculation unit 7, the second angle calculation unit 8, and the irradiation control unit 9 in Fig. 2 described above are hereinafter referred to as the "information acquisition unit 3, etc." The information acquisition unit 3, etc. is realized by a processing circuit 81 shown in Fig. 35. That is, the processing circuit 81 includes an information acquisition unit 3 that acquires various information, a travel trajectory estimation unit 4 that estimates a travel trajectory IL, a proximity target position setting unit 6 that sets a proximity target position FP, a first angle calculation unit 7 that calculates a first angle θp, an inner reference position acquisition unit 5 that acquires an inner reference position TP, a second angle calculation unit 8 that calculates a second angle θtp, and an illumination control unit 9 that controls illumination of the first headlight 10 based on the proximity target position FP and the inner reference position TP when a difference Δθ between the first angle θ and the second angle θtp is less than a threshold value θth, controls illumination of the first headlight 10 based on the proximity target position FP when the difference Δθ is equal to or greater than the threshold value θth, and controls illumination of the second headlight 11 based on the inner reference position TP. The processing circuit 81 may be implemented with dedicated hardware, or may be implemented with a processor that executes a program stored in a memory. Examples of the processor include a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, and a DSP (Digital Signal Processor).

[0169] When the processing circuit 81 is a dedicated hardware, the processing circuit 81 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination of these. Each function of the information acquisition unit 3 and the like may be realized by a circuit in which the processing circuits are distributed, or the functions of each unit may be realized by a single processing circuit.

[0170] When the processing circuit 81 is a processor, the functions of the information acquisition unit 3 and the like are realized by a combination with software and the like. Note that the software and the like includes, for example, software, firmware, or software and firmware. The software and the like is written as a program and stored in a memory. As shown in FIG. 36, a processor 82 applied to the processing circuit 81 realizes the functions of each unit by reading and executing a program stored in a memory 83. That is, the light distribution control device 12 includes a memory 83 for storing a program that, when executed by the processing circuit 81, results in the execution of the following steps: acquiring various information, estimating a travel path IL, setting a proximity target position FP, calculating a first angle θp, acquiring an inner reference position TP, calculating a second angle θtp, and controlling the illumination of the first headlamp 10 based on the proximity target position FP and the inner reference position TP when a difference Δθ between the first angle θ and the second angle θtp is less than a threshold value θth, controlling the illumination of the first headlamp 10 based on the proximity target position FP when the difference Δθ is equal to or greater than the threshold value θth, and controlling the illumination of the second headlamp 11 based on the inner reference position TP. In other words, this program can be said to cause a computer to execute the procedures and methods of the information acquisition unit 3, etc. Here, the memory 83 may be, for example, a non-volatile or volatile semiconductor memory such as a Random Access Memory (RAM), a Read Only Memory (ROM), a flash memory, an Erasable Programmable Read Only Memory (EPROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), an HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disc), a drive device for any of these, or any storage medium to be used in the future.

[0171] The above describes a configuration in which each function of the information acquisition unit 3, etc. is realized either by hardware or software, etc. However, the present invention is not limited to this, and a configuration in which a part of the information acquisition unit 3, etc. is realized by dedicated hardware and another part is realized by software, etc. For example, the information acquisition unit 3 can realize its functions by a processing circuit 81 as dedicated hardware, an acquisition circuitry such as an interface, and the other functions can be realized by the processing circuit 81 as a processor 82 reading and executing a program stored in a memory 83.

[0172] As described above, the processing circuitry 81 can realize each of the above-mentioned functions by hardware, software, or a combination of these.

[0173] It should be noted that the embodiments and modifications may be freely combined, and the embodiments and modifications may be modified or omitted as appropriate.

[0174] The above description is illustrative in all respects and is not restrictive. It is understood that countless variations not illustrated can be envisioned. [Explanation of symbols]

[0175] 4 driving trajectory estimation unit, 5 inner reference position acquisition unit, 6 proximity target position setting unit, 7 first angle calculation unit, 8 second angle calculation unit, 9 irradiation control unit, 10 first headlamp, 10a, 11a irradiation range, 11 second headlamp, 12 light distribution control device, 14 surveillance camera, 15 attention direction estimation unit, 16 correction unit, 21 vehicle, 22 forward direction, 23, 24 direction, 26 attention range, 31 driver, 32 candidate position, CP reference corresponding position, FP proximity target position, FP1 first proximity target position, FP2 second proximity target position, FPd attention position, IL driving trajectory, TP, ETP inner reference position, TP1 first inner reference position, TP2 second inner reference position, θd, θdr attention direction, θp first angle, θtp second angle.

Claims

1. A light distribution control device that controls light distribution from a vehicle using map information, a travel trajectory estimation unit that estimates a travel trajectory of the vehicle on a curved road on which the vehicle will travel in the future based on the map information; a target position setting unit that sets a target position along the travel path to which the vehicle should travel; a first angle calculation unit that calculates a first angle between a forward direction of the vehicle and a direction from the vehicle to the target position; an inside reference position acquisition unit that acquires an inside reference position that is associated in advance with an inner periphery portion of the curved road; a second angle calculation unit that calculates a second angle between the forward direction of the vehicle and a direction from the vehicle to the inner reference position; an illumination control unit that controls illumination of a first headlamp of the vehicle based on the target position and the inner reference position when a difference between the first angle and the second angle is less than a threshold value, and controls illumination of the first headlamp based on the target position when the difference is equal to or greater than the threshold value, and controls illumination of a second headlamp of the vehicle based on the inner reference position; A light distribution control device comprising:

2. The light distribution control device according to claim 1, A light distribution control device, wherein the inner reference position is the position of the end of the inner circumference portion as seen from the vehicle located at a predetermined point just before the curve, or a position on a straight line passing through the end and the vehicle located at the predetermined point.

3. The light distribution control device according to claim 2, The light distribution control device, wherein the position on the straight line is a position of an intersection between the straight line and the driving trajectory, or a position of an intersection between the straight line and an outer periphery of the curved road.

4. The light distribution control device according to claim 1, The target position setting unit is The light distribution control device reduces a distance between the target position and the vehicle before the vehicle reaches a reference corresponding position on the travel trajectory that corresponds to the inner reference position.

5. The light distribution control device according to claim 1, The target position setting unit is A light distribution control device that increases the distance between the target position and the vehicle as the vehicle moves away beyond a reference corresponding position on the travel trajectory that corresponds to the inner reference position.

6. The light distribution control device according to claim 1, The inner reference position is a first inner reference position that is pre-associated with the inner periphery portion of the curve; a second inner reference position that is preliminarily associated with the inner periphery portion of the curve and is farther from the vehicle than the first inner reference position; Including, The target position setting unit is A light distribution control device which, when a distance between a first target position, which is the target position based on the first inner reference position, and a second target position, which is the target position based on the second inner reference position, is less than a threshold value, changes a second gaze time for setting the second target position from the same time as the first gaze time before the change of the first gaze time for setting the first target position is completed.

7. The light distribution control device according to claim 1, An attention direction estimation unit that estimates an attention direction in which a driver of the vehicle is paying attention, The irradiation control unit is a light distribution control device that increases the illuminance of a range of the illumination range of the first headlight and the illumination range of the second headlight that corresponds to the attention direction.

8. The light distribution control device according to claim 7, The attention direction estimation unit is A first attention direction is estimated based on an output of a surveillance camera in a room of the vehicle, and a second attention direction is estimated based on an output of a steering angle sensor of the vehicle; The irradiation control unit is A light distribution control device that, when the first attention direction and the second attention direction are obtained, uses the second attention direction with priority over the first attention direction.

9. The light distribution control device according to claim 1, an attention direction estimation unit that estimates an attention direction in which a driver of the vehicle is paying attention; a correction unit that performs a correction to bring the target position closer to a position corresponding to the attention direction, based on the attention direction; The light distribution control device further comprises:

10. A light distribution control method for controlling light distribution from a vehicle using map information, comprising: Based on the map information, a travel trajectory of the vehicle on a curved road that the vehicle will travel in the future is estimated; A target position along the travel path to which the vehicle should travel is set; Calculating a first angle between a forward direction of the vehicle and a direction from the vehicle to the target location; Acquire an inside reference position that is pre-associated with an inner periphery portion of the curved road; calculating a second angle between the forward direction of the vehicle and a direction from the vehicle to the inner reference position; A light distribution control method comprising: controlling illumination of a first headlight of the vehicle based on the target position and the inner reference position when a difference between the first angle and the second angle is less than a threshold value; controlling illumination of the first headlight based on the target position when the difference is equal to or greater than the threshold value; and controlling illumination of a second headlight of the vehicle based on the inner reference position.

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